Strategies towards statistically robust interpretations of in situ U–Pb zircon geochronology
MetadataShow full item record
Zircon U–Pb geochronology has become a keystone tool across Earth science, arguably providing the gold standard in resolving deep geological time. The development of rapid in situ analysis of zircon (via laser ablation and secondary ionization mass spectrometry) has allowed for large amounts of data to be generated in a relatively short amount of time and such large volume datasets offer the ability to address a range of geological questions that would otherwise remain intractable (e.g. detrital zircons as a sediment fingerprinting method). The ease of acquisition, while bringing benefit to the Earth science community, has also led to diverse interpretations of geochronological data. In this work we seek to refocus U–Pb zircon geochronology toward best practice by providing a robust statistically coherent workflow. We discuss a range of data filtering approaches and their inherent limitations (e.g. discordance and the reduced chi-squared; MSWD). We evaluate appropriate mechanisms to calculate the most geologically appropriate age from both 238U/206Pb and 207Pb/206Pb ratios and demonstrate the cross over position when chronometric power swaps between these ratios. As our in situ analytical techniques become progressively more precise, appropriate statistical handing of U–Pb datasets will become increasingly pertinent.
This open access article is distributed under the Creative Commons license http://creativecommons.org/licenses/by-nc-nd/4.0/
Showing items related by title, author, creator and subject.
Cavosie, Aaron; Valley, J.; Kita, N.; Spicuzza, M.; Ushikubo, T.; Wilde, Simon (2011)The oxygen isotope ratios (δ18O) of most igneous zircons range from 5 to 8‰, with 99% of published values from 1345 rocks below 10‰. Metamorphic zircons from quartzite, metapelite, metabasite, and eclogite record δ18O ...
Cavosie, A.; Valley, J.; Kita, N.; Spicuzza, M.; Ushikubo, T.; Wilde, Simon (2011)The oxygen isotope ratios (d18O) of most igneous zircons range from 5 to 8%, with 99% of publishedvalues from 1345 rocks below 10%. Metamorphic zircons from quartzite, metapelite, metabasite, and eclogite record d18O ...
Monazite trumps zircon: applying SHRIMP U–Pb geochronology to systematically evaluate emplacement ages of leucocratic, low-temperature granites in a complex Precambrian orogenPiechocka, A.; Gregory, C.; Zi, J.; Sheppard, S.; Wingate, M.; Rasmussen, Birger (2017)© 2017, The Author(s). Although zircon is the most widely used geochronometer to determine the crystallisation ages of granites, it can be unreliable for low-temperature melts because they may not crystallise new zircon. ...